Glucose meter tests are generally accurate, but the accuracy value is related to the quality of the meter itself and whether it is calibrated regularly. There may be a slight difference between the blood glucose measured by the meter and the blood glucose from the vein, but this does not usually affect the monitoring of blood glucose. Glucose meters should be taken to the hospital once a year to be calibrated, compared and corrected with the venous blood glucose. If the error is large, you need to look for the cause or replace the meter. Nowadays, the quality of blood glucose meters sold on the market varies, the price difference is also very big, and some even buy blood glucose test strips free of charge for the blood glucose meter. Generally speaking, blood glucose meters with high prices and good brands will have higher accuracy. Under the premise of timely calibration, if a patient’s blood sugar is high or low when using a blood glucose meter, it is recommended to go to the hospital in time for examination and treatment.